wadswosth



M. OR IDGE 8v 8.. WADSWORTH.

OSGILLATING STEAM ENGINE.

No. 26,664. Patented Jan, 3, 1860.

crank; E the crank shafts; F is the valve or M. CRIDGE AND S. \VADSXVORTI-I,

or rr'r'rsBUne, PENNSYLVANIA STEAM-ENGINE.

Specification of Letters Patent No. 26,664, datedq'wanuary 3,

To all whom it. may concern:

Be it known that we, MATTHEW Garner and SAMUEL, WADSWORTH, both of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Oscillating Steam Engines; and we hereby declare that the following is a full, clear, exact description ofithe same, reference being had tothe accompanying drawings, making a part of this specification.

The engine represented inthe drawings, and to which our improvement has reference, is of' the class of engines, generally known by the name of sidepipe engines in which the steam is admitted and also escapes from the cylinder, through a stationary valve or sidepipe at the side of the cylinder; the distribution ofthe steam, or the opening and closing of the steamports being effected by the oscillations of the cylinder.

Our invention consists in an improved arrangement of keeping the steamport-surfaces of the sidepipe and of the cylinderin proper steamtight contact in such a manner, that theexpansion and contraction of the cylinder and sidepipe, caused by variations in their temperature, has no influence thereon.

To enable others skilled in the art, to

make and use our invention, we willproceed to describe its construction and operation. I

In the accompanying drawings: Figure 1, is a perspective view of the engine; Fig. 2, a vertical section through the sidepipe, trunnions of the cylinder, and part of the framework, showing also a side view of the cylinder; Fig. 3 is a horizontal section of the same parts, taken in the line I-II (Fig. 2) Fig. 4, is a View of the backside of thesidepipe showing also a section through the line IIIIV (Fig. 2).

In all these figures the same letters of reference are marked on alike parts.

A, A, A is the framework of the engine, composed of the base A, and stands A A; B is the cylinder; 0 the piston rod; D; the

sidepipe f f pipes for the introduction of the steam into, and for the escape of the same from the sidepipe. b, b, are the steamport faces of the sidepipe, resting against the port faces a, a, of the cylinder.

G, G, are the trunnions of the cylinder.

The trunnion G is forked, so as to allowfl a I 1 strong bar H, to pass transversely and freely I e, is a set screw, through the center of the; I

through it. ThebarH-is firml bolted onthe s trunnion itisprovidedwi th a jamnutg, and its pomt bearsagalnst the transverse bar H at apoint which is; exactly I I least nearly) in one planeywithl the steam ports-or contact-surfaoes I (a; and I b) of the 3 cylinder and sidepipe; Ii, tare pivots secured to: the flanges h, h, 1 (cast on theframework) a 1 and tapped intothe projections 7c, icyprog a vided at the sidepipe' I These pivots are 'w opposite eachother and at right angleswith I a line a, ,8, (Fig. @Q taken through the cenll ter of the steanrportsurfaces bet thefiside? pipe; By these pivotsI thevsidepipe,F, iskept1 1 I 175 f in its position, and they vprevent i-t' from turning I sidewise; I or following the oscilla-v tions of the cylinder; but they allow the t surfaces?) 6 of the-sidepipe,to accommodate y I themselves to the surfaces d 11 of thecylin der.

v C The portholes in the sidepipe (which are 3 indicated at m and mpFig.14$)=,wandinthe- I cylinder, through which thei steam isyad 1 mitted and exhausted,arearranged pre-f cisely ins the same manner as theplord-i nary sidepipe en-ginesnxthe cylinder portholes coming in; alternate: communication with the sidepipe-portholesfhy the oscilla tions of the cylinder. II I In the described GHgHlGhOHI' improvement consists in the arranging the set screw 6, v

(passing through the center of the trunnion), to butt against a transverse bar, (H)

at a point (00), which "isinone planewith the port or valve surfaces (at, a,;and b, 6,).

It is obvious, thathereby, the cylinder may l (in consequence of variations in itstemperature) expand and contract, without affecting in the least the true position or proper 3 4? contact of the surfaces at, a, and b, b; the

point x, and consequently the surfaces which are in one plane with it, being the starting point, from whichjthe expansion 1 acts away (as indicated byarrow y)xand toward which the contraction acts back again (as indicated byarrow z).

Our improvement further consists inanranging the pivots z', i,(which form the a points of abutment for thesidepipe,) ;in I

such a manner, that they are also in one plane with the contact surfacesb, b, for the g I purpose of allowing the sidepipe to expand 3 and contract, without producing thereby any efiect on the correct and proper contact of the same, with the surfaces a, a, of the cylinder, the expansion acting away from these points and the contraction toward them, in a similar manner as above de scribed in reference to the cylinder. Thus the port surfaces of the cylinder as well as of the sidepipe, being not influenced by the expansion and contraction of those parts, will always preserve a perfect con tact with each other under an invariable degree of pressure. The proper degree of pressure, sufiicient to make the joint between the port surfaces steam tight, is effected by the set screw, which in pressing against the transverse bar H, draws the cylinder against the sidepipe.

The described arrangement may be modified in various ways, without changing the distinguishing feature of our improvement. Thus Fig. 5, shows the transverse bar H fastened to the sidepipe (in place of securing it to the framework, as above shown) but the point :0, on which the screw 6 acts, is in a line (or nearly so) with the port surfaces (0 a and b b of the cylinder and sidepipe (as has been the case in the arrangement above described).

Fig. 6, shows a modification of the parts for keeping the side pipe in its position; in place of using pivots (i 2') (as above described), there are two projections Z, Z, cast or fastened on the framework, the points of which enter into cavities in the flanges 0, 0, provided at the sidepipe, and thus form the abutment for the same. The end points of the projections Z, Z, have to be in one plane (or nearly so) with the port surfaces.

The expansion and contraction of the cylinder and sidepipe has always been a very serious objection in sidepipe engines as arranged heretofore; to keep the port surfaces in proper contact it required a constant attention in the way of adjusting, and readjusting, in order to avoid leakage at one time, and an undue pressure between them at another time. By our improved arrangement this objection is completely overcome. We finally wish to state, that, having subjected our improved arrangement to practical trials, it fully and practically exhibited the advantages, we claim for it, and which We have fully set forth herein. 7 7 7 We are perfectly aware, that set screws and other equivalent means have been used before and applied in various ways, for the purpose of keeping the sidepipe and cylinder faces in contact, we therefore do not claim any of these means, or of an arrangement of the same, already known; but

WVhat we do claim and desire to secure by Letters Patent, is:

1. The arrangement of a set screw, or its equivalent, passing through the center of the trunnion and butting againsta transverse bar H at a point, which is in one plane (or nearly so) with the portor valve-surfaces (a, a, Z), 6) of the cylinder and sidepipe, in the manner substantially as de scribed and for the purpose herein set forth.

2. We also claim, the arrangement of the pins 2', i, or other means, for the support of the sidepipe, F, in such a manner, that the points of abutment are also in one plane (or nearly so) with the portor valve-surfaces of the cylinder and sidepipe; substantially as described and for the purpose herein fully set forth.

MATTHEW CRIDGE. SAMUEL WADSVVORTH. Witnesses:

HENRY MOSER, AUG. HARTJE. 

